Water Quality Monitoring

The Deer Creek Watershed Management Plan reflects management measures that when implemented are intended to improve the water quality within the watershed. Monitoring programs are designed to track the progress in meeting load reduction goals and attaining water quality standards. One of the challenges in water quality monitoring is to be able to demonstrate a link between the implementation of management measures and water quality improvements. Therefore, monitoring results will be used to track long term changes in Deer Creek.

Rain Garden Monitoring

One monitoring program seeks to assess the effectiveness of pollutant removal by three Best Management Practice (BMP) demonstration projects. Monitoring is done before and after the construction of the BMP demonstration projects to determine the effectiveness of the BMPs. Monitoring the BMPs will help determine the overall benefits to Deer Creek if more of these practices were implemented over time.

Water Quality Monitoring in Deer Creek and its Tributaries

Another monitoring program is being conducted to monitor water quality changes in Deer Creek and its tributaries. The Litzsinger Road Ecology Center (LREC) Stream Team led by Danelle Haake collects data on a monthly basis at seven points in the upper Deer Creek watershed, including the tributaries of Twomile Creek and Sebago Creek. This type of sampling is ideal for getting a picture of typical conditions in various portions of Deer Creek and its tributaries.

Map of monitoring locations
Map of water quality monitoring locations in the Deer Creek watershed. Go to larger map.

It is important to note that LREC monitors do not collect samples during the high-flow periods associated with storm flow. This is because the purpose of the monitoring at LREC is to track long-term baseline conditions during “normal” flow periods. Avoidance of high-flow conditions results in not measuring water quality during some of the periods with the greatest loads of pollutants.

Water quality monitoring has indicated that high concentrations of chloride have occurred during the winter months when many individuals and private and public organizations use sodium chloride to de-ice driveways, parking lots, and walkways. In addition, there have been several instances in which the saturation of dissolved oxygen was greater than 200%. This elevation in dissolved oxygen levels is often caused by the excess production of oxygen by algae or macrophytes during photosynthetic processes. This is symptomatic of a system in which supersaturated daytime conditions are followed by sags in dissolved oxygen as overnight respiration causes oxygen concentrations to plummet once the sun goes down and photosynthesis ceases.

In addition, Metropolitan St. Louis Sewer District (MSD) currently monitors 35 sites throughout its service area for the Stream Monitoring Program. The purpose of the Stream Monitoring Program is to gather information during storm and non-storm events, to assess the impacts of CSOs/SSOs and gather background data for these water bodies. Currently the goal for the monitoring program is to monitor all streams monthly. The Deer Creek watershed is one of the areas being sampled as part of this Stream Monitoring Program. There are a total of four MSD monitoring sites within the Deer Creek watershed: they are located on Deer Creek, Black Creek, Twomile Creek, and Shady Grove Creek.

The data collected from the LREC Stream Team and MSD will be analyzed in three year intervals by Washington University in St. Louis to determine water quality changes in Deer Creek.

Learn more

Download an analysis of samples [694 KB] collected by the LREC Stream Team prepared by Danelle Haake.

Download Chapter 10 [39 KB] of the Deer Creek Watershed Management Plan to learn more about monitoring programs. 

Download Evaluation of the Effectiveness of Three Rain Garden Projects in the Deer Creek Basin, St. Louis, Missouri [1.8 MB] by Robert Criss.